1. field of the Invention
This invention relates generally to surgical devices and procedures; and, more specifically, to surgically implantable devices for expanding skin tissue and mucous membrane.
2. Description of the Prior Art
The expansion of skin is an observed phenomenon. Abdominal skin is seen to expand in pregnancy and in progressing obesity.
It is known to take advantage of this phenomenon. One device, developed by C. Radovan causes skin to expand by surgically implanting an inflatable bag under the skin. The bag is connected by a tube to a reservoir which is also implanted. The bag is incrementally inflated by hypodermically injecting a fluid into the reservoir from time to time. Inflation of the bag causes the skin tissue to expand.
Such a device and procedure have important advantages. Skin tissue needed for plastic surgery can be generated adjacent its site of use. The expanded skin is partially loosened and stretched to the area of surgery. Thus, such surgery can be accomplished with skin having color and texture characteristics similar to the repaired area, and the repair is made with a minimum of additional disturbance to the vascular supply of the expanded skin.
The device and procedure of Radovan have certain disadvantages. The requirement for an inflatable bag attached by a tube to a reservoir, all of which are to be surgically implanted, limits such a device to larger projects. For instance, such a device would be impractical for use in expanding tissue for cleft lip or palate repair of an infant.
Incremental inflation of the bag by hypodermic means is an inconvenience to both the patient and the physician, requiring a regular schedule of visits over a period of several weeks. Each subsequent injection of fluid into the reservoir can result in additional discomfort for the patient. Each such subsequent injection can also provide an opportunity for an undesirable infection.